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Copyright by Patricia Lucile Jones 2014 The Dissertation Committee for Patricia Lucile Jones Certifies that this is the approved version of the following dissertation: Foraging Decisions by Eavesdropping Bats Committee: Michael J. Ryan, Supervisor Rachel A. Page, Co-Supervisor Lawrence E. Gilbert Molly E. Cummings Ulrich G. Mueller Foraging Decisions by Eavesdropping Bats by Patricia Lucile Jones, B.A. Dissertation Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy The University of Texas at Austin May, 2014 Dedication To my parents and my sister, I love you. To my grandmother, Pat Fouraker, I miss you. Acknowledgements There are many people who made this possible. First, thank you to my two wonderful supervisors Mike Ryan and Rachel Page for your support, encouragement, and advice throughout. I am deeply grateful. Thank you also to all the members of my committee for their helpful feedback: Ulrich Mueller, Molly Cummings and Larry Gilbert. I also feel very lucky to have been able to work with two amazing biologists who recently passed away: Björn Siemers and Elizabeth Kalko. You have been an inspiration to me and I wish I could have had more time to learn from you. Thank you to all who helped me in the field: Victoria Flores, Teague O’Mara, Tess Driessens, Jay Falk, Christina Buelow, Sarah Richman, May Dixon, Kristina Ottens, and Teia Schwietzer. I am very grateful for your good company, late night carrot cake, trips to the beach, and lots of laughter. You kept me sane! Thank you to all of the wonderful members of the Ryan Lab who have provided a happy atmosphere and given me good advice: Pam Willis, Karin Akre, Monica Guerra, Sofia Rodriguez, Audrey Stewart, Meghan Still, Bret Pasch, and Heidi Smith Parker. You are all fantastic scientists and great people. I will miss working with you. I also thank my roommates over the years in Austin: Laura Crothers, Bonnie Waring, Kelly Pierce and their respective felines. Thank you for being so supportive and making our house home. To the members, past and present, of the Austin Rowing Club’s Women’s Competitive Team, thank you for all the workouts, the races, and the breakfast tacos. You have been an essential retreat for me and I have loved rowing with you. And to my family, Mom, Dad and Lee. I could not have made it this far without your love and support and I can never thank you enough. v Foraging Decisions by Eavesdropping Bats Patricia Lucile Jones, Ph.D. The University of Texas at Austin, 2014 Supervisors: Michael J. Ryan and Rachel A. Page Animals forage in complex environments in which they must constantly make decisions about which resources to approach and which to avoid. Many factors can influence these foraging decisions including perception and cognition. Predators that locate prey by eavesdropping on prey mating calls face a challenging foraging task because they must be able to identify which species-specific prey signals indicate palatable prey. My thesis investigates such foraging decisions in eavesdropping bats. The Neotropical fringe-lipped bat, Trachops cirrhosus, locates its frog and katydid prey by eavesdropping on the prey’s calls. One of the prey of T. cirrhosus in Panamá is the túngara frog, Physalaemus pustulosus, that can make simple calls consisting of a “whine” alone, or complex calls which are a whine followed by 1-7 “chucks”. In my first chapter I examine what components of frog calls bats use to identify and localize them. I assess how bats respond to the two components of the complex calls of P. pustulosus, and report that, unlike female frogs, bats respond to the chuck component alone but preferentially approach the whine. Next, I examine how response to prey cues is affected by prey availability by assessing the response of T. cirrhosus to geographically and seasonally variable prey. I find population and seasonal differences in response to some prey cues but not to other cues. Trachops cirrhosus can also learn novel prey cues from exposure to vi a conspecific tutor (social learning). My third chapter examines the conditions that influence when bats socially learn novel prey cues. I discover that bats are more likely to use social information to learn novel prey cues when the cue they are currently using to find food is unreliable. In my fourth and final chapter I address how eavesdropping can contribute to the evolution and diversification of bats by investigating the potential of eavesdropping on katydid calls for niche partitioning in two closely related bat species, the European greater and lesser mouse-eared bats, Myotis myotis and Myotis blythii oxygnathus. Together these studies highlight the role of cognition in foraging decisions and consider the consequences of eavesdropping for niche partitioning. vii Table of Contents List of Tables ...........................................................................................................x List of Figures ........................................................................................................ xi INTRODUCTION .................................................................................................1 Background .....................................................................................................1 Research Questions .........................................................................................4 CHAPTER 1 ...........................................................................................................7 Do frog-eating bats perceptually bind the complex components of frog calls? ......7 Abstract ...........................................................................................................7 Introduction .....................................................................................................8 Methods...........................................................................................................9 Results ...........................................................................................................13 Discussion .....................................................................................................16 Acknowledgements .......................................................................................18 CHAPTER 2 .........................................................................................................20 Population and seasonal variation in response to prey calls by an eavesdropping bat .......................................................................................................................20 Abstract .........................................................................................................20 Introduction ...................................................................................................21 Methods.........................................................................................................25 Results ...........................................................................................................31 Discussion .....................................................................................................39 Acknowledgements .......................................................................................46 CHAPTER 3 .........................................................................................................47 When to approach novel prey cues? Social learning strategies in frog-eating bats47 Abstract .........................................................................................................47 Introduction ...................................................................................................48 viii Methods.........................................................................................................50 Results ...........................................................................................................58 Discussion .....................................................................................................63 Acknowledgements .......................................................................................66 CHAPTER 4 .........................................................................................................67 Behavioral evidence for eavesdropping on prey song in two Palearctic sibling bat species ...........................................................................................................67 Abstract .........................................................................................................67 Introduction ...................................................................................................68 Materials and Methods ..................................................................................71 Results ...........................................................................................................77 Discussion .....................................................................................................82 Acknowledgements .......................................................................................86 SUMMARY AND DISCUSSION ........................................................................87 REFERENCES .....................................................................................................91 ix List of Tables Table 1: Number of landing events on speaker for all 7 bats that showed landing behaviour

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